It's instructive to compare WTA rankings against Championship Race rankings. The WTA rankings measure points over the past year (52 weeks) while the Race rankings measure points since November 2012, which was the start of the 2013 WTA season.
For any player, a Race ranking that is higher than her WTA ranking generally means that the player has gotten better results more recently--in other words, that she's in better form.
With the first five months of the season (November 2012-March 2013) now complete, here's how the rankings of selected Croatian players compare. The first number is their Race ranking (past five months; NR means they haven't played or earned any points during that time); the second number is their WTA ranking (ie, past 52 weeks).
Under this system,
in relative terms the most out-of-form player is Martic (

) while the most in-form player is Vrljic (

).
In-form players
59 ... 171 ... Tomljanovic
103 ... 163 ... Mrdeza
121 ... 224 ... Vrljic
139 ... 237 ... Savic
239 ... 404 ... Pandzic
424 ... 742 ... Lekaj
469 ... 868 ... Konjuh
About the same
81 ... 88 ... Vekic
111 ... 100 ... Lucic-Baroni
Out-of-form players
438 ... 91 ... Martic
773 ... 622 ... Njiric
NR ... 441 ... Abramovic
NR ... 628 ... Akiki
NR ... 883 ... Mijacika
NR ... 955 ... Banovec